[Effect of an exercise program targeting knee pain on medical costs of elderly community-dwelling adults]

Objectives The aim of this study was to examine the effect of an exercise program targeting knee pain on longitudinal medical costs (MC) of elderly community-dwelling adults.Methods A community-based health program using specific exercises for improving knee pain was held from January to February, 2015. Twenty-eight individuals participated in the program (intervention group) and seventy individuals were selected from the respondents of a health and lifestyle survey by matching age, sex, and baseline value of severity of knee pain as a control group. Twenty individuals from the intervention group and twenty-nine from the control group were included in the final analysis. The changes in MC from 2014 to 2018 were compared between the two groups using a linear mixed-effects model.Results The effect of the program on MC, estimated as a change from the baseline in 2014, showed a reduction of -5.6×10³ yen/person (95% CI: -39.2-28.0) for the entire four-year period after the intervention. However, this difference was not significant. The changes in MC each year after the intervention were 9.3×10³ yen/person (95% CI: -39.6-58.3) in 2015, -2.0×10³ yen/person (95% CI: -44.4-40.5) in 2016, -10.3×10³ yen/person (95% CI: -42.5-21.9) in 2017, and 8.2×10³ yen/person (95% CI: -39.1-55.4) in 2018.Conclusion The exercise program did not show a clear benefit in reducing the MC of elderly community-dwellers during the four years after the intervention. Further research with longer study durations and larger sample populations would be necessary to determine the effect of such intervention programs on MC.